The brouhaha started when Mr Tonich waited 25 minutes for a banana smoothie last Sunday.

His post on his public Facebook page that "Wild Fig Cafe Scarborough still holds the title for the worst service in Perth" prompted others to chime in with their own criticisms.

Elle Demasi, the girlfriend of AFL star Nic Naitanui, was among them. "Yep! I waited 30mins there for a take away iced coffee with no cream or ice cream lol," she wrote.

Greer Marns, co-owner of the beachfront eatery, retaliated with six signs dotted around the cafe all poking fun at their unhappy customer.

"Come in and experience what one guy on Facebook (let's call him Mr Itch) thinks is the worst service in Perth," read a sign at the cafe's entrance.

Another sign offered an "apology": "Public apology to Paul Tonich who waited 25 minutes for his smoothie last Sunday. We are sorry Paul. Rest assured, we have all been suitably SPANKED.

Another sign read: "Need a real estate agent? Contact local agent Paul Tonich. He guarantees to sell your home in 25 minutes."

"The Gin and Tonich, with extra lemon, can be a little bitter," another sign read.

Mr Tonich said he was shocked by the reaction and The Wild Fig had "over-stepped the mark".

"I'm not vindictive," he said. "I just gave my opinion and then the public gave their opinion.

"It's a two-line post that turned into mayhem. It's not my fault everyone else took the opportunity to voice their bad experiences. I have the names of the other 76 upset customers on my post."

Ms Marns said she put out the signs because Mr Tonich wouldn't give her the right of reply on his Facebook page.

"Our customers were all talking about it," she said. "We thought it's out in the open, let's put it out there and have a bit of fun with it."

Since being inundated with negative feedback on their Facebook page, and learning that the story had been published on News Ltd websites around Australia, the owners of The Wild Fig Café reached out an olive branch to Mr Tonich.

“So, where do we go from here? Well, perhaps the answer has been staring us in the face for the past week. We’ve asked Paul Tonich, Perth identity and well-known business coach, to help us improve our service in exchange for a lifetime supply of our scandalous smoothies,” they announced on thefig.com.au.